the droplet only contributes to \(F^{\prime}(0)\) through the first term
this term is always positive for \(\gamma_{m} < \gamma_{d}\) (which is always
true), meaning the droplet can never be assistive to the flat-curved
membrane transition
as \(V_{d}\) gets infinitely large, this effect goes to 0
droplet helps late in internalization, not initial bending
show what parameters affect the h coordinate and ∆F magnitude at which the
free energy barrier is located
(IDEA) at finite size, when does thermodynamics improve by having the droplet?
may not be able to answer
if we separate F into F_droplet and F_non-droplet, what value of
gamma_m/gamma_d does ∆F_droplet(h=1) = 0
y-axis: volume of droplet
x-axis: gamma_m/gamma_d
droplet volume and interfacial tensions set energy barrier characteristics
how does this compare to opposing energy magnitudes?
how do droplet energy magnitudes compare to other known energy contributions in CME
this is where we make comparisons to physiological ranges of energy
discussion
initial barrier might actually be physiologically important and align with
experimental observations
CME is defined by highly variable initiation/recruitment stage followed by
fast, reproducible internalization stage
as the droplet grows, the energy barrier shifts to lower h
droplet assists CME progression through newly exposed membrane
true for both alternative toy models
is the continuum model relevant yet? maybe show a simulation initializing
around the predicted energy barrier where the droplet is necessary for
completion
what features are parameter-independent?
the wetting component always is net negative free energy and negative
slope at h=0
what features are parameter-dependent?
energy from droplet collapses on wetting component as droplet volume
approaches infinity
net change in energy from droplet depends on interfacial tensions, coat
area, droplet volume
droplet can produce energy barrier
always true for constant area model
sometimes true for constant curvature model
in both models, barrier gets smaller/earlier as volume increases or
wetting/surface tension ratio increases
for continuum model, compare with/without droplet?
what do the droplet parameters need to be in order to make an impact on
endocytosis energetics?
lots of phase diagrams
what do experimental measurements of these droplet parameters predict about
the impact of the droplet in endocytosis?
combination of FRAP and merging dynamics to estimate surface tension and
viscosity in cytoplasm
unlikely to have time for this, but set up synthetic membrane experiments
with purified proteins and induced curvature
introduction
papers with data I could use to help introduce the model and motivate the
geometrical constraints
evidence of condensates participating in CME (from retreat slide)
which proteins does the model represent?
I have my own time lapse data of liquid-like dynamics for both of these
proteins
model explanation (fig. 1)
results (figs. 2-?)
references
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